JP2002274938A - Dielectric ceramic composition, electronic part and method for manufacturing the part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dielectric ceramic composition which is excellent in reductive resistance at firing has excellent capacity-temperature characteristics after firing and can prolong the accelerated life of insulation resistance. SOLUTION: The dielectric ceramic composition has at least a main component containing dielectric oxides of compositions expressed by (Sr1-x Cax ) O}m .(Ti1-y Zry )O2 and the fourth subcomponent containing oxides of R, wherein R is at least one kind selected from Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. In the above formula of the main component, m, x and y are the molar ratios in the composition and satisfy the relation of 0.94<m<1.02, 0<=x<=1.00 and 0<=y<=0.20. The proportion of the fourth subcomponent to 100 mol of the main component is 0.02 mol<=(fourth subcomponent)<2 mol in terms of R in the oxides.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric ceramic composition used, for example, as a dielectric layer of a multilayer ceramic capacitor, an electronic component using the dielectric ceramic composition as a dielectric layer, and a method of manufacturing the same. .

[0002]

2. Description of the Related Art A multilayer ceramic capacitor, which is an example of an electronic component, is formed by printing a conductive paste on a green sheet made of a predetermined dielectric ceramic composition, and laminating a plurality of green sheets printed with the conductive paste. The green sheet and the internal electrode are integrally fired and formed.

[0003] Conventional dielectric ceramic compositions are reduced when fired in a neutral or reducing atmosphere having a low oxygen partial pressure,
It had the property of becoming a semiconductor. For this reason, when manufacturing a multilayer ceramic capacitor, it has been necessary to perform firing in an oxidizing atmosphere having a high oxygen partial pressure. Along with this, as an internal electrode material that is fired simultaneously with the dielectric porcelain composition, an expensive noble metal that does not melt at the temperature at which the dielectric porcelain composition sinters and is not oxidized even when fired in an oxidizing atmosphere (For example, palladium or platinum) must be used, which has been a great obstacle to reducing the price of the manufactured multilayer ceramic capacitor.

On the other hand, in order to use an inexpensive base metal (for example, nickel or copper) as a material for an internal electrode, it does not become a semiconductor even when fired at a low temperature in a neutral or reducing atmosphere. It is necessary to develop a dielectric porcelain composition that has excellent reducibility, has a sufficient relative dielectric constant after firing, and has excellent dielectric properties (for example, a small rate of change in capacitance with temperature).

Hitherto, various proposals have been made as dielectric ceramic compositions in which a base metal can be used as a material of an internal electrode.

For example, Japanese Unexamined Patent Publication No. 63-224108
In the report, (Sr_1-xCa_x) _m(Ti_1-y
Zr_y) O₃Dielectric oxide of composition shown by
0.30 ≦ x ≦ 0.50, 0.03 ≦ y ≦ 0.2
0, 0.95 ≦ m ≦ 1.08) as a main component.
Per 100 parts by weight of Mn as MnO
₂0.01 to 2.00 parts by weight in conversion, SiO₂To
0.10 to 4.00 parts by weight of the dielectric porcelain composition
It has been disclosed.

Japanese Patent Application Laid-Open No. Sho 63-224109 discloses a dielectric ceramic composition containing 0.01 to 1.00 parts by weight of ZnO in addition to the above-mentioned main component, in addition to the above-mentioned Mn and SiO _2. It has been disclosed.

Furthermore, in JP-A 4-206109 _{discloses, (Sr 1-x Ca x} ) m (Ti 1-y Zr
_y ) a dielectric oxide having a composition represented by O ₃ (however,
0.30 ≦ x ≦ 0.50, 0.00 ≦ y ≦ 0.20,
(0.95 ≦ m ≦ 1.08) as a main component, and a dielectric ceramic composition having a powder particle size in a range of 0.1 to 1.0 μm is disclosed.

Further, Japanese Patent Publication No. 62-24388
In the report, (MeO)_kTiO₂Dielectric of composition shown by
Body oxides (where Me is Sr, Ca and Sr + Ca
A metal selected from the group consisting of 1.00 and 1.04).
And the glass component with respect to 100 parts by weight of the main component.
As Li₂O, M (where M is BaO, CaO
At least one metal oxide selected from and SrO
Product) and SiO₂ Is used at a predetermined molar ratio.
A dielectric porcelain composition containing 2 to 10.0 parts by weight is disclosed.
It is.

[0010]

However, in any of the dielectric ceramic compositions described in these publications, the accelerated life of insulation resistance after firing is short, and the dielectric ceramic composition is made of a base metal such as nickel by using the dielectric ceramic composition. When a multilayer ceramic capacitor having internal electrodes is manufactured, there is a problem that the reliability of the obtained multilayer ceramic capacitor is reduced.

In the case where a multilayer ceramic capacitor having a base metal internal electrode is manufactured using the dielectric ceramic composition, especially when the dielectric layer is made thinner, the insulation resistance (IR) deteriorates. There is also a problem that the defect rate of the initial insulation resistance of the obtained multilayer ceramic capacitor increases.

A first object of the present invention is to provide a dielectric ceramic composition which is excellent in reduction resistance during firing, has excellent capacity-temperature characteristics after firing, and can improve the accelerated life of insulation resistance. It is to provide. A second object of the present invention is to provide an electronic component such as a chip capacitor having excellent capacitance-temperature characteristics, an improved accelerated life of insulation resistance, and improved reliability. A third object of the present invention is to provide a capacitor having excellent capacitance-temperature characteristics, maintaining the reliability required for an electronic component, and hardly deteriorating the insulation resistance even when the dielectric layer is made thinner. An object of the present invention is to provide a method of manufacturing an electronic component such as a chip capacitor having a low resistance defect rate.

[0013]

In order to achieve the above object, a dielectric ceramic composition according to the present invention is characterized in that Δ (Sr _{1−
x Ca x) O} m ·} (Ti 1-y Zr y) O
A main component containing a dielectric oxide having a composition represented by Formula ₂ ;
(Where R is Sc, Y, La, Ce, P
r, Nd, Pm, Sm, Eu, Gd, Tb, Dy, H
and at least one fourth subcomponent containing at least one selected from the group consisting of o, Er, Tm, Yb and Lu), wherein the composition has a composition molar ratio in a formula contained in the main component. Symbols m, x, and y are in a relationship of 0.94 <m <1.02, 0 ≦ x ≦ 1.00, 0 ≦ y ≦ 0.20, and the ratio of the fourth subcomponent to 100 mol of the main component is It is characterized in that the ratio is 0.02 mol ≦ the fourth subcomponent <2 mol in terms of R in the oxide.

Preferably, R contained in the fourth subcomponent is
Is an oxide of Sc, Y, Ce, Dy, Ho, Er, T
It is at least one oxide of m, Yb and Lu.
Preferably, the dielectric porcelain composition according to the present invention contains particles in which the oxide of R contained in the fourth subcomponent is substantially uniformly distributed in the particles.

Preferably, the dielectric porcelain composition according to the present invention comprises oxides of V, Nb, W, Ta and Mo and / or
Alternatively, the composition further includes a first subcomponent containing at least one compound selected from these compounds which become oxides after firing, and the ratio of the first subcomponent to 100 mol of the main component is calculated in terms of a metal element in the oxide. , 0.01 mol ≦ first subcomponent <2 mol.

Preferably, the dielectric porcelain composition according to the present invention further comprises a second subcomponent containing an oxide of Mn and / or a compound which becomes an oxide of Mn when fired, with respect to 100 moles of the main component. The ratio of the second subcomponent is 0 mol ≦ the second subcomponent <4 mol in terms of the metal element in the oxide.

Preferably, the dielectric ceramic composition according to the present invention
The object is SiO₂, MO (where M is Ba, Ca,
At least one element selected from Sr and Mg),
Li ₂O and B₂O₃At least selected from
A third subcomponent containing at least one of
When the ratio of the third subcomponent to the mole is oxide,
0 mol <third subcomponent <15 mol. The third subcomponent is
It is thought to function as a sintering aid. Features of the third subcomponent
Preferred embodiments are as follows. More preferred
Preferably, the dielectric ceramic composition according to the present invention comprises (S
r_p, Ca_1-p ) SiO₃(However, p is 0.3
≦ p ≦ 1), wherein the main component is
The ratio of the third subcomponent to 100 moles is
By calculation, 0 mol <third subcomponent <15 mol. This kind of
The third subcomponent is considered to function as a sintering aid.

Preferably, the dielectric porcelain composition according to the present invention has a capacitance change rate with respect to temperature (ΔC) of at least -2000 to 85 ° C.
0 ppm / ° C, preferably -1500 to 0 ppm / ° C,
More preferably, it is -1000 to 0 ppm / ° C. However, the reference temperature of the capacitance C is 20 ° C.

In order to achieve the above object, an electronic component according to the present invention is an electronic component having a dielectric layer, wherein the dielectric layer is made of any one of the above dielectric ceramic compositions. It is characterized by the following.

Preferably, the electronic component according to the present invention has a capacitor element main body in which the dielectric layers and the internal electrode layers are alternately laminated.

Preferably, in the electronic component according to the present invention, the conductive material contained in the internal electrode layer is nickel or a nickel alloy.

In order to achieve the above object, a method of manufacturing an electronic component according to the present invention comprises a step of preparing a dielectric paste using any of the above-described dielectric ceramic compositions, and preparing a paste for an internal electrode. A step of alternately laminating the dielectric paste and the paste for internal electrodes to obtain a laminate, and forming the laminate at an oxygen partial pressure of 10 ⁻¹⁰ to 10.
^-3 Pa, preferably ^{10 -1} 0 ^~6 × ^{10 -5} P
a, more preferably a firing step of firing in an atmosphere of 10 ^{−6 to} 6 × 10 ⁻⁵ Pa to obtain a sintered body, and a step of heat-treating the sintered body.

In order to achieve the above object, a method of manufacturing an electronic component according to the present invention comprises a step of preparing a dielectric paste using any of the above-described dielectric ceramic compositions, and preparing a paste for an internal electrode. A step of alternately laminating the dielectric paste and the internal electrode paste to obtain a laminate, and a firing step of firing the laminate to obtain a sintered body,
Heat-treating the sintered body in an atmosphere having an oxygen partial pressure of 10 ⁻⁴ Pa or more, preferably 10 ⁻¹ to 10 Pa.

Preferably, in the method of manufacturing an electronic component according to the present invention, nickel or a nickel alloy is used as the internal electrode paste. In the dielectric ceramic composition according to the present invention, Si contained in the third subcomponent
Each of O ₂ , MO, Li ₂ O, and B ₂ O ₃ is intended to have at least such a composition after firing, and also includes a compound which becomes an oxide thereof after firing.

[0025]

In the dielectric porcelain composition according to the present invention, a predetermined amount of a specific fourth subcomponent is added to a main component containing a dielectric oxide having a specific composition having a relatively low m.
It has excellent resistance to reduction during firing, has excellent capacity-temperature characteristics after firing, and has an improved accelerated life of insulation resistance as compared with the case where the fourth subcomponent is not added.

The electronic component such as the chip capacitor according to the present invention has a dielectric layer composed of the dielectric ceramic composition according to the present invention, and therefore has excellent capacitance-temperature characteristics.
Moreover, the accelerated life of the insulation resistance is improved, and the reliability of the electronic component is improved.

In the method for manufacturing an electronic component according to the present invention, a laminate in which a dielectric ceramic composition having a specific composition having a relatively low m is laminated is prepared by subjecting a laminate having an oxygen partial pressure of 10 ⁻¹⁰ to 10 ⁻³ P
By firing in an atmosphere of a predetermined oxygen partial pressure such as a, the dielectric layer has excellent capacity-temperature characteristics, and maintains the reliability required for an electronic component while maintaining the dielectric layer at, for example, 4 μm between layers.
Even when the thickness is reduced to about m, the insulation resistance of the obtained electronic component such as a chip capacitor hardly deteriorates, and the occurrence of a defective rate of the initial insulation resistance can be reduced.

In the method for manufacturing an electronic component according to the present invention, the ratio
Dielectric ceramic composition of specific composition having relatively low m is laminated
The sintered body obtained by firing the laminated body is subjected to an oxygen partial pressure.
10 ^-4Heat in an atmosphere with a predetermined oxygen partial pressure such as Pa or more
By performing the treatment (annealing), excellent capacity temperature characteristics
While maintaining the reliability required for electronic components.
If the dielectric layer is thinned to, for example, about 4 μm between layers,
Resistance is not easily deteriorated even if
Generation can be reduced efficiently.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on embodiments shown in the drawings. FIG. 1 is a cross-sectional view of a multilayer ceramic capacitor according to an embodiment of the present invention, FIG. 2 is a graph showing the capacitance-temperature characteristics of Sample 13 as an example of the present invention, and FIG. 3 is Sample 3 as an example of the present invention. FIG. 4 is a graph showing the relationship between the distance from the grain boundary and the concentration of Y ₂ O ₃ in Sample 3 which is an example of the present invention. FIG. 5 is a TEM image of Sample 9 which is an example of the present invention. FIG. 6 shows the distance from the grain boundary and Y ₂ O in Sample 9 which is an example of the present invention.
₃ graph showing the relationship between the concentration of, and the presence or absence of Y added as a fourth subcomponent 7, a graph showing the relationship between the high temperature load lifetime, in the sample 12 and 13 is an embodiment of FIG. 8 is the invention 9A and 9B are graphs showing the relationship between the added amount of V and the high-temperature load life time. FIGS. 9A and 9B show the yield rate of the oxygen partial pressure and the initial insulation resistance in the heat treatment step when the thickness of the dielectric layer is changed. FIG. 10 is a graph showing the relationship between (Sr _p , Ca _1-p ) SiO ₃ as a third subcomponent.
6 is a graph showing the relationship between the content ratio of r and the yield rate of the initial insulation resistance (IR) of the capacitor sample.

[0030] Multilayer Ceramic Capacitor As shown in FIG. 1, a multilayer ceramic capacitor 1 as an electronic device according to an embodiment of the present invention, the configuration of the capacitor dielectric layers 2 and internal electrode layers 3 stacked alternately It has an element body 10. At both ends of the capacitor element body 10, a pair of external electrodes 4 are formed, each of which is electrically connected to the internal electrode layers 3 alternately arranged inside the element body 10. The shape of the capacitor element body 10 is not particularly limited, but is usually a rectangular parallelepiped. In addition, the dimensions are not particularly limited, and may be appropriately determined according to the application.
Usually, (0.6 to 5.6 mm) x (0.3 to 5.0 m
m) × (0.3 to 1.9 mm).

The internal electrode layers 3 are laminated so that each end face is exposed alternately on the surface of the two opposing ends of the capacitor element body 10. The pair of external electrodes 4 are formed at both ends of the capacitor element body 10 and connected to the exposed end faces of the alternately arranged internal electrode layers 3 to form a capacitor circuit.

[0032]Dielectric layer 2 The dielectric layer 2 contains the dielectric ceramic composition of the present invention.
The dielectric ceramic composition of the present invention has a Δ (Sr_1-xCa
_x) O｝_m・ (Ti _1-yZr_y) O₂Indicated by
And a main component containing a dielectric oxide having the following composition:
(However, R is Sc, Y, La, Ce, Pr, Nd,
Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, T
m, Yb and Lu).
And at least a fourth subcomponent. At this time, oxygen
The amount of (O) is slightly deviated from the stoichiometric composition of the above formula.
Good.

In the above formula, x is 0 ≦ x ≦ 1.00, preferably 0.30 ≦ x ≦ 0.50. x represents the number of Ca atoms, and it is possible to arbitrarily shift the phase transition point of the crystal by changing x, that is, the Ca / Sr ratio. Therefore, the capacitance temperature coefficient and the relative permittivity can be arbitrarily controlled. When x is in the above range, the phase transition point of the crystal exists near room temperature, and the temperature characteristics of the capacitance can be improved. However, in the present invention, the ratio between Sr and Ca is arbitrary, and may contain only one.

In the above formula, y is 0 ≦ y ≦ 0.20, preferably 0 ≦ y ≦ 0.10. By setting y to 0.20 or less, a decrease in the relative dielectric constant is prevented. Although y is a number of Zr atoms, hard ZrO which is reduced compared to TiO ₂
Substitution of ₂ tends to further increase reduction resistance. However, in the present invention, Zr does not always need to be contained, and may contain only Ti.

In the above formula, m is 0.94 <m <1.0
2, preferably 0.97 ≦ m ≦ 1.015. By setting m to be larger than 0.94, it is possible to prevent the semiconductor from being converted into a semiconductor when fired in a reducing atmosphere.
By setting it to less than 02, the effect of adding the fourth subcomponent can be obtained.

The difference between the dielectric ceramic composition of the present invention and the conventional dielectric ceramic composition is that m is 0.94 <m <1.0.
In a range of 2, that is, a range where m is relatively low, a predetermined fourth
The point is that the auxiliary component is added in a predetermined amount. By adding a predetermined amount of the predetermined fourth subcomponent, m of the main component is 0.94 <m
Low-temperature baking is possible without deteriorating the dielectric properties in the range of <1.02, and even when the dielectric layer is thinned, the accelerated life of the insulation resistance (high-temperature load life) can be improved, and the reliability is greatly improved. Can be improved. As a result, miniaturization of capacitors
High capacity can be achieved.

In the present invention, the fourth subcomponent is an oxide of R (where R is Sc, Y, La, Ce, Pr, Nd,
Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, T
m, Yb and Lu). The fourth subcomponent has the effect of improving the high-temperature load life (accelerated life of insulation resistance) and has a thin layer (for example, 4 μm).
This also has an effect of improving the initial IR failure rate when the above-mentioned is performed. From the viewpoint of improving the defect rate, Sc, Y, Ce, D
More preferably, at least one oxide of y, Ho, Er, Tm, Yb and Lu is contained.

In the present invention, the ratio of the fourth subcomponent to 100 mol of the main component is 0.02 mol ≦ the fourth subcomponent <2 mol, preferably 0.02 ≦ the fourth subcomponent in terms of R in the oxide. Component ≦ 0.6. The ratio of the fourth subcomponent is determined by R
By setting the range of 0.02 mol ≦ the fourth subcomponent <2 mol in terms of conversion, the accelerated life of the insulation resistance can be improved when m is in the range of 0.94 <m <1.02.

In the dielectric ceramic composition according to the present invention, it is preferable that the oxide of R contained in the fourth subcomponent contains particles which are substantially uniformly distributed in the particles. In the present invention, a predetermined amount of the fourth subcomponent is contained with respect to the main component. In particular, the fourth subcomponent contains particles in which the oxide of R is substantially uniformly distributed in the grains. This is more effective in improving the high-temperature load life (accelerated life of insulation resistance).

As the value of m of the main component becomes smaller, the oxide of R tends to contain particles which are substantially uniformly distributed in the grains.

Further, in the dielectric ceramic composition according to the present invention, the first ceramic containing one or more oxides of V, Nb, W, Ta and Mo and / or a compound which becomes these oxides after firing. It is preferable that an auxiliary component is further added. The first subcomponent acts as a substance that lowers the sintering temperature and improves the accelerated life of insulation resistance. The ratio of the first subcomponent with respect to 100 mol of the main component is 0.01 mol ≦ first subcomponent <2 mol, preferably 0.04 mol ≦ first subcomponent ≦ 0. 6 moles. By setting the ratio of the first subcomponent in the range of 0.01 mol ≦ the first subcomponent <2 mol in terms of the metal element in the oxide, m is 0.94 <m <1.02.
Within this range, the accelerated life of the insulation resistance can be further improved. Preferably, as the first subcomponent, an oxide of V and / or a compound which becomes an oxide by firing is 0.01% in terms of V.
More than 2 moles and less than 2 moles, more preferably about 0.04 moles to 0.6 moles. By including such a specific first subcomponent in the above range, it is more effective to improve the high temperature load life.

Further, in the dielectric ceramic composition according to the present invention, an oxide of Mn (for example, MnO) and / or a compound (for example, MnCO
It is preferable that the second subcomponent containing ₃ ) is further added. This second subcomponent has the effect of promoting sintering,
In addition, it also has an effect of lowering the initial insulation resistance (IR) defect rate when the dielectric layer 2 is thinned to, for example, about 4 μm. The ratio of the second subcomponent to 100 mol of the main component is 0 mol ≦ second subcomponent <
4 mol, preferably 0.05 mol ≦ second subcomponent ≦ 1.4
Is a mole. When the addition amount of the second subcomponent is 4 mol or more, the initial insulation resistance tends not to be obtained, and when the addition amount of the second subcomponent is 0 mol ≦ the second subcomponent <4 mol, the addition amount is small. As the amount increases, the occurrence of the initial IR failure rate can be reduced, and as the amount of addition decreases, the rate of change in capacitance with temperature can be reduced.

Further, in the dielectric ceramic composition according to the present invention, SiO ₂ , MO (where M is Ba, C
a, at least one element selected from Sr and Mg), and a third subcomponent containing at least one element selected from Li ₂ O and B ₂ O ₃ is preferably further added. The third subcomponent mainly acts as a sintering aid, but has an effect of improving the defect rate of the initial insulation resistance when the thickness is reduced. From the viewpoint of improving the defect rate, Li
It is more preferable to contain ₂ O. Further, from the viewpoint of improving the defective _{rate, (Sr p, Ca 1-} p) SiO
More preferably, ₃ is contained. In this case, p is 0.3 ≦ p ≦ 1, preferably 0.5 ≦ p ≦ 1
It is. p represents the number of Sr atoms. By increasing the value of p, it is possible to improve the yield rate of the initial IR. The ratio of the third subcomponent to 100 mol of the main component is 0 mol <third subcomponent <1 in terms of oxide.
5 mol, preferably 0.2 mol ≦ third subcomponent ≦ 6 mol. It is effective to improve the sinterability by increasing the addition amount of the third subcomponent to more than 0 mol. By decreasing the addition amount to less than 15 mol, a decrease in the relative dielectric constant is suppressed, and a sufficient capacity is obtained. Can be secured.

Various conditions such as the number of layers and the thickness of the dielectric layer 2 shown in FIG. 1 may be appropriately determined according to the purpose and application. The dielectric layer 2 is composed of grains and a grain boundary phase, and the average grain size of the grains of the dielectric layer 2 is 1 to 5 μm.
It is preferable that there is a degree. This grain boundary phase is usually an oxide of a material constituting the dielectric material or the internal electrode material,
An oxide of a material separately added, or an oxide of a material mixed as an impurity during the process is used as a component and is usually made of glass or glass.

Internal Electrode Layer 3 The conductive material contained in the internal electrode layer 3 is not particularly limited, but a base metal can be used since the constituent material of the dielectric layer 2 has reduction resistance. As the base metal used as the conductive material, Ni or a Ni alloy is preferable. The Ni alloy is selected from Mn, Cr, Co and Al.
An alloy of at least one kind of element and Ni is preferable.
The content is preferably 95% by weight or more. In addition,
Ni or a Ni alloy may contain various trace components such as P, Fe, and Mg in an amount of about 0.1% by weight or less. The thickness of the internal electrode layer may be appropriately determined according to the use or the like, but is usually preferably 0.5 to 5 μm, particularly preferably about 1 to 2.5 μm.

External Electrode 4 The conductive material contained in the external electrode 4 is not particularly limited, but usually Cu or Cu alloy, Ni or Ni alloy or the like is used. Incidentally, Ag, Ag-Pd alloy or the like can of course be used. In this embodiment, inexpensive Ni, C
u and their alloys are used. The thickness of the external electrode may be appropriately determined according to the application and the like.
m is preferable.

Manufacturing Method of Multilayer Ceramic Capacitor A multilayer ceramic capacitor using the dielectric ceramic composition of the present invention can be produced in the same manner as a conventional multilayer ceramic capacitor.
A green chip is produced by a normal printing method or a sheet method using a paste, fired, and then external electrodes are printed or transferred and fired. Less than,
The manufacturing method will be specifically described.

First, a paste for a dielectric layer, a paste for an internal electrode, and a paste for an external electrode are manufactured.

Dielectric Layer Paste The dielectric layer paste may be an organic paint obtained by kneading a dielectric material and an organic vehicle, or may be an aqueous paint.

As the dielectric raw material, a raw material constituting the main component and a raw material constituting the first to fourth subcomponents are used according to the composition of the dielectric ceramic composition according to the present invention described above.
Sr, Ca, Ti, Z
An oxide of r and / or a compound which becomes an oxide by firing is used. As a raw material constituting the first subcomponent,
One or more single oxides or composite oxides selected from oxides of V, Nb, W, Ta and Mo and / or compounds that become these oxides after firing are used. As a raw material constituting the second subcomponent, an oxide of Mn and / or a single oxide or a composite oxide of a compound which becomes an oxide of Mn by firing is used. The raw materials constituting the third subcomponent include SiO ₂ and MO (where M is
At least one selected from Ba, Ca, Sr and Mg
), At least one compound selected from the group consisting of Li ₂ O and B ₂ O ₃ . As a raw material constituting the fourth subcomponent, an oxide of R (where R is S
c, Y, La, Ce, Pr, Nd, Pm, Sm, Eu,
Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu
At least one selected from the group consisting of

Examples of the compound that becomes an oxide upon firing include carbonates, nitrates, oxalates, and organometallic compounds. Of course, an oxide and a compound that becomes an oxide by firing may be used in combination. The content of each compound in the dielectric raw material may be determined so that the composition of the dielectric ceramic composition described above after firing is obtained. These raw material powders usually have an average particle diameter of about 0.0005 to 5 μm.

The organic vehicle is obtained by dissolving a binder in an organic solvent, and the binder used in the organic vehicle is not particularly limited, and may be appropriately selected from various ordinary binders such as ethyl cellulose and polyvinyl butyral. In addition, the organic solvent used at this time is not particularly limited, and may be appropriately selected from organic solvents such as terpineol, butyl carbitol, acetone, and toluene according to a method such as a printing method or a sheet method.

The water-based paint is obtained by dissolving a water-soluble binder, a dispersant and the like in water. The water-based binder is not particularly limited, and may be polyvinyl alcohol, cellulose, water-soluble acrylic resin, emulsion, or the like. May be selected as appropriate.

Internal electrode paste and external electrode paste The internal electrode paste is made of a conductive material made of the above-mentioned various conductive metals or alloys or various oxides, organometallic compounds, resinates, etc. which become the above-mentioned conductive material after firing. And the organic vehicle described above. The external electrode paste is also prepared in the same manner as the internal electrode paste.

The content of the organic vehicle in each of the above-mentioned pastes is not particularly limited, and may be a usual content, for example, about 1 to 5% by weight of a binder and about 10 to 50% by weight of a solvent. Each paste may contain additives selected from various dispersants, plasticizers, dielectrics, insulators, and the like, as necessary.

When a printing method is used, a dielectric chip and an internal electrode paste are laminated and printed on a substrate such as polyethylene terephthalate, cut into a predetermined shape, and then separated from the substrate to obtain a green chip. On the other hand, when the sheet method is used, a green sheet is formed using a dielectric paste, an internal electrode paste is printed thereon, and these are laminated to form a green chip.

Next, the green chip is subjected to binder removal processing and firing.

The binder removal treatment may be performed under ordinary conditions. In particular, when a base metal such as Ni or a Ni alloy is used as the conductive material of the internal electrode layer, the temperature rise rate is set to 5 in an air atmosphere. ~ 3
00 ° C / hour, more preferably 10 to 100 ° C / hour,
The holding temperature is 180 to 400 ° C, more preferably 200 to 400 ° C.
The temperature is maintained at 300 ° C. for 0.5 to 24 hours, more preferably 5 to 20 hours.

The firing atmosphere of the fired green chip may be appropriately determined according to the type of the conductive material in the internal electrode layer paste, but when a base metal such as Ni or a Ni alloy is used as the conductive material,
The oxygen partial pressure of the firing atmosphere is preferably 10 ⁻¹⁰ to 10
^-3 Pa, more preferably 10 ^{-10 to} 6 × 10
⁻⁵ Pa, more preferably 10 ^{−6 to} 6 × 10 ⁻⁵ P
a. If the oxygen partial pressure at the time of firing is too low, the conductive material of the internal electrode may be abnormally sintered and cut off. If the oxygen partial pressure is too high, the internal electrode may be oxidized. By adjusting the oxygen partial pressure to 10 ^{−10 to} 6 × 10 ⁻⁵ Pa, the capacitor has excellent capacity-temperature characteristics, and the accelerated life of the insulation resistance is improved, so that the reliability of the obtained multilayer ceramic capacitor 1 is improved. Can be enhanced. Especially when the oxygen partial pressure is 1
By adjusting the pressure to 0 ^{−6 to} 6 × 10 ⁻⁵ Pa, the multilayer ceramic capacitor 1 has excellent capacitance-temperature characteristics.
Even if the dielectric layer 2 is thinned to, for example, about 4 μm between layers while maintaining the reliability required for the above, the insulation resistance of the obtained capacitor 1 is hardly deteriorated, and the occurrence of a defective rate of the initial insulation resistance can be reduced. .

The holding temperature for firing is 1000 to 1400
° C, more preferably from 1200 to 1380 ° C. If the holding temperature is too low, the densification becomes insufficient, and if the holding temperature is too high, the capacitance-temperature characteristics deteriorate due to the interruption of the electrodes due to abnormal sintering of the internal electrodes or the diffusion of the internal electrode material.

Other firing conditions include a heating rate of 50 to 500 ° C./hour, more preferably 200 to 300 ° C.
° C / hour, the temperature holding time is 0.5-8 hours, more preferably 1-3 hours, the cooling rate is 50-500 ° C / hour, more preferably 200-300 ° C / hour, and the firing atmosphere is a reducing atmosphere. It is desirable to use, for example, a mixed gas of nitrogen gas and hydrogen gas after humidification as the atmospheric gas.

When firing in a reducing atmosphere, it is desirable to perform annealing (heat treatment) on the sintered body of the capacitor chip.

Annealing (Heat Treatment) Annealing is a process for reoxidizing the dielectric layer, and can increase the insulation resistance. The oxygen partial pressure of the annealing atmosphere is preferably 10 ⁻⁴ Pa or more, more preferably 10 ⁻¹ to 10 Pa. If the oxygen partial pressure is too low, reoxidation of the dielectric layer 2 becomes difficult, and if the oxygen partial pressure is too high, the internal electrode layer 3 may be oxidized. In particular, when heat-treating a sintered body obtained by firing the dielectric ceramic composition of the present invention, the oxygen partial pressure is set to 10 ^-1 to 10 Pa.
In this case, the dielectric layer is thinned to a thickness of, for example, about 4 μm while maintaining the reliability (accelerated life of insulation resistance) required for the multilayer ceramic capacitor 1 while maintaining excellent capacitance temperature characteristics. Even when the multilayer ceramic capacitor 1 is obtained,
This is more effective in reducing the occurrence of a defective rate of the initial insulation resistance.

The holding temperature at the time of annealing is 1100 ° C. or lower, more preferably 500 to 1100 ° C. If the holding temperature is too low, re-oxidation of the dielectric layer becomes insufficient, insulation resistance deteriorates, and its accelerated life tends to be shortened. On the other hand, if the holding temperature is too high, not only is the internal electrode oxidized, the capacity is reduced, but also the reaction occurs with the dielectric substrate, and the capacity-temperature characteristics, insulation resistance and accelerated life tend to be deteriorated. Incidentally, the annealing may be constituted only by the temperature raising step and the temperature lowering step. In this case, the temperature holding time is zero, and the holding temperature is synonymous with the maximum temperature.

Other annealing conditions include a temperature holding time of 0 to 20 hours, more preferably 6 to 10 hours,
The cooling rate is 50 to 500 ° C./hour, more preferably 10 to 500 ° C./hour.
It is preferable that the temperature is 0 to 300 ° C./hour, and the annealing atmosphere gas is, for example, moistened nitrogen gas.

As in the case of the above-described firing, a wetter or the like can be used to humidify the nitrogen gas or the mixed gas in the binder removal treatment and the annealing step. It is desirable to be set to ° C.

The binder removal treatment, firing and annealing may be performed continuously or independently of each other. In the case of performing these steps continuously, the atmosphere is changed without cooling after the binder removal treatment, then the temperature is raised to the holding temperature at the time of firing, and firing is performed. When the temperature reaches the above, it is more preferable to change the atmosphere and perform the annealing treatment. On the other hand, when these are performed independently, it is necessary to raise the temperature in a nitrogen gas or humidified nitrogen gas atmosphere to the holding temperature at the time of the binder removal treatment, and then change the atmosphere and continue the temperature increase. Preferably, after cooling to the annealing holding temperature, it is preferable to change to a nitrogen gas or humidified nitrogen gas atmosphere again and continue cooling. Further, regarding the annealing, the atmosphere may be changed after the temperature is raised to the holding temperature in a nitrogen gas atmosphere, or the entire annealing process may be performed in a humidified nitrogen gas atmosphere.

The fired capacitor body obtained as described above is polished by, for example, barrel polishing or sand blasting, and the external electrode paste is printed or transferred and fired to form the external electrode 4. The firing condition of the external electrode paste is preferably, for example, about 600 minutes to about 800 ° C. for about 10 minutes to 1 hour in a humidified mixed gas of nitrogen gas and hydrogen gas. Then, if necessary, a coating layer (pad layer) is formed on the surface of the external electrode 4 by plating or the like.

The ceramic capacitor 1 of the present embodiment manufactured as described above is mounted on a printed circuit board by soldering or the like, and is used for various electronic devices.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments at all, and it is needless to say that the present invention can be implemented in various modes without departing from the gist of the present invention. It is.

For example, in the above-described embodiment, the multilayer ceramic capacitor is exemplified as the electronic component according to the present invention. However, the electronic component according to the present invention is not limited to the multilayer ceramic capacitor, but may be a dielectric ceramic composition having the above composition. Any material may be used as long as it has a dielectric layer made of a material.

[0072]

Next, the present invention will be described in more detail by way of examples which embody the embodiments of the present invention. However,
The present invention is not limited to only these examples.

Example 1 First, as a starting material for producing a dielectric material, a main component material (SrCO) having an average particle size of 0.1 to 1 μm was used.
₃ , CaCO ₃ , TiO ₂ , ZrO ₂ ) and first to fourth subcomponent raw materials. Carbonate (second sub-component: MnCO ₃ ) is used as a raw material of MnO, and oxides (first sub-component: V ₂ O ₅ , third sub-component: Si) are used as other raw materials.
O ₂ + CaO, fourth subcomponent: Y ₂ O ₃ ) was used. In addition, SiO ₂ + CaO as the third subcomponent is S
Similar characteristics were obtained using CaSiO ₃ obtained by wet mixing iO ₂ and CaO with a ball mill for 16 hours, drying, firing in air at 1150 ° C., and further wet grinding with a ball mill for 100 hours. .

These raw materials are represented by the composition formula ｛(Sr_1-x
Ca_x) O｝_m・ (Ti_1-y Zr_y) O
₂(Main component) + V₂O₅(First subcomponent) + MnC
O₃(Second subcomponent) + (SiO₂+ CaO) (third
Subcomponent) + Y₂O₃(4th sub-component)
It was weighed so that the composition afterwards became the compounding ratio shown in Tables 1-4.
After that, each of them is ball milled for about 16 hours
Dielectric porcelain set by wet mixing and drying
A product (dielectric material) was obtained.

100 parts by weight of the dried dielectric material thus obtained, 4.8 parts by weight of acrylic resin, 40 parts by weight of methylene chloride, 20 parts by weight of ethyl acetate, and 6 parts by weight of mineral spirit And 4 parts by weight of acetone were mixed with a ball mill to form a paste, thereby obtaining a dielectric layer paste.

Next, N having an average particle size of 0.2 to 0.8 μm
100 parts by weight of i-particles, 40 parts by weight of an organic vehicle (8 parts by weight of ethyl cellulose dissolved in 92 parts by weight of butyl carbitol), and 10 parts by weight of butyl carbitol are kneaded with a three-roll mill to form a paste. An electrode layer paste was obtained.

Next, Cu particles 1 having an average particle size of 0.5 μm
00 parts by weight and an organic vehicle (ethyl cellulose resin 8
35 parts by weight of butyl carbitol dissolved in 92 parts by weight of butyl carbitol) and 7 parts by weight of butyl carbitol were kneaded into a paste to obtain an external electrode paste.

Next, a 6 μm thick green sheet is formed on a PET film using the above dielectric layer paste, and the internal electrode layer paste is printed thereon.
The green sheet was peeled off from the PET film. Next, these green sheets and a protective green sheet (without printing the internal electrode layer paste) are laminated,
The green chip was obtained by pressure bonding. The number of stacked sheets having internal electrodes was four.

Next, the green chip is cut into a predetermined size, the binder is removed, baked, and annealed (heat treatment).
To obtain a multilayer ceramic fired body. The binder removal treatment was performed under the conditions of a heating time of 15 ° C./hour, a holding temperature of 280 ° C., a holding time of 8 hours, and an air atmosphere. The firing was performed at a heating rate of 200 ° C./hour and a holding temperature of 1200 to 13
80 ° C., holding time 2 hours, cooling rate 300 ° C./hour, humidified N ₂ + H ₂ mixed gas atmosphere (oxygen partial pressure is 2 ×
10 ^{−7 to} 5 × 10 ⁻⁴ Pa). Annealing was performed under the conditions of a holding temperature of 900 ° C., a temperature holding time of 9 hours, a cooling rate of 300 ° C./hour, and a humidified N ₂ gas atmosphere (oxygen partial pressure is 3.54 × 10 ⁻² Pa). Note that a wetter with a water temperature of 35 ° C. was used for humidifying the atmosphere gas during firing and annealing.

Next, after polishing the end face of the laminated ceramic fired body by sand blasting, the external electrode paste was transferred to the end face, and fired at 800 ° C. for 10 minutes in a humidified N ₂ + H ₂ atmosphere. Form
A sample of the multilayer ceramic capacitor having the configuration shown in FIG. 1 was obtained.

The size of each sample thus obtained was 3.2 mm × 1.6 mm × 0.6 mm, the number of dielectric layers sandwiched between the internal electrode layers was 4, and the thickness was 4 μm.
m, and the thickness of the internal electrode layer was 2 μm. The following characteristics were evaluated for each sample.

The relative permittivity (εr) and the insulation resistance (IR) of a capacitor sample were measured at a reference temperature of 25 ° C. using a digital LCR meter (4274A manufactured by YHP) at a frequency of 1 kHz and an input signal level (measurement voltage) of 1 Vrms. Under the conditions, the capacitance was measured. Then, a relative dielectric constant (no unit) was calculated from the obtained capacitance, the electrode dimensions of the capacitor sample, and the distance between the electrodes. Thereafter, using a insulation resistance meter (R8340A manufactured by Advantest), insulation resistance IR after applying DC 50 V to the capacitor sample at 25 ° C. for 60 seconds was measured, and the measured value, the electrode area and the thickness of the capacitor sample, and the like were measured. , The specific resistance ρ (unit: Ωcm) was calculated. The results are shown in Tables 1 to 4. As an evaluation, the relative dielectric constant εr is an important characteristic for producing a small-sized and high-dielectric-constant capacitor, and was set to 180 or more, more preferably 200 or more. The specific resistance ρ was 1 × 10 ¹² Ωcm or more. The value of the relative permittivity εr is determined by the number of capacitor samples n = 10
It was determined from the average of the values measured using the individual pieces. The value of the specific resistance ρ was an average value of the specific resistances of 10 non-defective products.

Capacitance Temperature Characteristic For a capacitor sample, using an LCR meter,
The capacitance at a voltage of 1 kHz and 1 V is measured, and when the reference temperature is set to 20 ° C., the capacitance change rate with respect to the temperature is −2000 to 0 ppm / ° C. within a temperature range of 20 to 85 ° C.
Was determined, and the results are shown in Tables 1 to 4.
The capacity change rate ΔC85 / C20 (ppm / ° C.) was calculated by the following equation 1. ΔC85 / C20 = ｛(C85-C
20) / C20｝ × (1/65) Equation 1 where Equation 1
Medium, C85 is capacitance at 85 ° C, C20 is 20 ° C
Represents the capacitance at. In addition, the capacitance change rate ΔC / C of the representative sample 13 of this example in the temperature range of −50 ° C. to + 150 ° C. was measured, and is graphed in FIG. The figure shows the rate of change based on the capacity at 20 ° C. As can be seen from the figure, it can be understood that good capacitance-temperature characteristics are exhibited.

High Temperature Load Life (Accelerated Life of Insulation Resistance ) The high temperature load life of the capacitor sample was measured by maintaining a DC voltage of 8 V / μm at 175 ° C. This high-temperature load life was evaluated for ten capacitor samples (thickness of the dielectric layer was 4 μm) and the average life time was measured. Table 1 shows the results
To Table 4 below. As an evaluation, the high temperature load life is particularly important when the dielectric layer is made thinner, and the time from the start of application until the resistance drops by one digit is defined as the life.

Observation of Dielectric Structure by TEM-EDS Sample 3 (m = 0.98) which is a typical composition of this example
FIG. 3 shows a TEM photograph of 5), and FIG. 4 shows the relationship between the distance (nm) from the grain boundary and the concentration (% by weight) of Y ₂ O ₃ in Sample 3. For comparison, a TEM photograph of Sample 9 (m = 1.02) is shown in FIG. 5, and the distance (nm) from the grain boundary in Sample 9 and Y
FIG. 6 shows the relationship with the concentration (% by weight) of ₂ O ₃ . In Sample 3, but the high temperature load life is greatly improved and 129 hours by Y addition, according to FIGS. 3 and 4, Y ₂ O
It was confirmed that No. ₃ was substantially uniformly distributed in the grains.
On the other hand, in sample 9, the high-temperature load life hardly changed to 2.2 hours even when Y was added, but according to FIGS. 5 and 6, Y ₂ O ₃ segregated at the grain boundaries and triple points, and uniformity was observed. Was not distributed.

[0086]

[Table 1]

[0087]

[Table 2]

[0088]

[Table 3]

[0089]

[Table 4]

The numbers of moles of the first to fourth subcomponents in Tables 1 to 4 are ratios with respect to 100 moles of the main component, and the number of moles of the first subcomponent is mole number of V. In Tables 1 to 4, in the numerical value of the specific resistance (ρ), “mE + n” is “m × 10”.
^{+ N} ". From the results shown in Table 1, the following is understood with respect to the added amount of the fourth subcomponent. If no Y is added as in sample 1 and the amount of Y added is 2 mol as in sample 7, the high temperature load life (the accelerated life of the insulation resistance) is insufficient. Samples 2 to 6 containing a predetermined amount of subcomponents have a sufficient relative dielectric constant and insulation resistance (resistivity), are not reduced even when fired in a reducing atmosphere, and have an internal electrode material of nickel. It can be confirmed that a dielectric porcelain composition which is not oxidized and has excellent resistance to reduction has been obtained, and has excellent capacity-temperature characteristics, and can improve the high-temperature load life (accelerated life of insulation resistance). It could be confirmed.

From the results shown in Tables 2 and 3, m
It is understood that the ratio of When m = 0.94 as in Sample 8, it was confirmed that the dielectric was reduced by firing in a reducing atmosphere, sufficient insulation resistance could not be obtained, and the capacitor did not function as a capacitor. On the other hand, when m = 1.02 as in Sample 9, even if the fourth subcomponent is contained in a predetermined amount, the high temperature load life (accelerated life of insulation resistance) is hardly affected. That is, when m is relatively high such as m = 1.02, it can be seen that the high temperature load life value hardly changes even when Y is added (see Table 2). From this, it was found that when the main component m was relatively low, the effect of the addition of Y was easily exhibited, which was effective in improving the high temperature load life. In Tables 2 and 3, Sample 3 shows an example of the present invention, and Samples 9-1, 9-2, 8, and 9 show comparative examples of the present invention.

From the results shown in Table 4, it is understood that the amount of the first subcomponent is as follows. If no V is added as in Sample 10, the high temperature load life time is extremely short. If the amount of V added is 2 mol as in Sample 15, the dielectric becomes a semiconductor, and the insulation resistance is insufficient. On the other hand, the samples of Samples 11 to 14 have a sufficient relative dielectric constant and insulation resistance, are not reduced even when fired in a reducing atmosphere, do not oxidize nickel as an internal electrode material, and have a resistance to reduction. It was confirmed that a dielectric ceramic composition having excellent properties was obtained, and that the capacity-temperature characteristics were excellent and that the high-temperature load life (accelerated life of insulation resistance) could be improved. MoO instead of V ₂ O _5
3 , WO ₃ , Ta ₂ O ₅ and Nb ₂ O ₅
Was added and evaluated under the same conditions as above, but almost the same results were obtained in each case. Sample 11
14 to 14 show Examples of the present invention, and Samples 10 and 15
Shows a comparative example of the present invention.

Example 2 In this example, a test was conducted to confirm the effect of the presence or absence of Y on the high temperature load life (accelerated life of insulation resistance). Specifically, x = 0.36 and y = 0 of the main component, the number of moles of the first subcomponent (in terms of V) = 0.1 mole, and the number of moles of the second subcomponent (in terms of Mn) = 0.37. Mole, third subcomponent (S
Except that the number of moles of iO ₂ + CaO = (2.5 + 2.5) moles, the m value of the main component was 0.985 (calcination temperature 1
200 ° C.) and 1.02 (calcining temperature of 1380 ° C.), the high-temperature load life (accelerated life of insulation resistance) when Y was not added (0 mol) and when 0.07 mol was added. It was measured. The results are shown in FIG. 7. As can be seen from FIG. 7, the effect of the addition of Y is higher in the case of m = 0.885 than in the case of m = 1.02 when the high temperature load life is improved. It was confirmed that it was remarkable.

Example 3 In this example, using the samples 12 and 13 shown in Table 4, the addition amount (in terms of V) of the first subcomponent (V ₂ O ₅ ) was changed to a high temperature load life (acceleration of insulation resistance). A test was conducted to confirm the effect on life. The results are shown in FIG. 8. As can be seen from FIG. 8, when the added amount of V is increased to 0.2 mol, the life time is 184 hours on average, and the life of the capacitor is smaller than when the added amount is small. It can be seen that the reliability is high. In addition, it was confirmed that the life was improved by 2000 times or more as compared with the case where the added amount was 0 mol.

Example 4 The main components m = 0.885, x = 0.36, y = 0, the first
The number of moles of the subcomponent (in terms of V) = 0.1 mole, the number of moles of the third subcomponent (SiO ₂ + CaO) = (2.5 + 2.5 moles), and the number of moles of the fourth subcomponent (in terms of Y) = 0. Except that the amount was set to 07 mol, the amount of MnCO ₃ added as the second subcomponent (in terms of Mn) was changed and evaluated as shown in Table 5. The results are shown in Table 5.

[0096]

[Table 5]

As shown in Table 5, the second subcomponent (Mn)
When the added amount of (converted) is 4 mol, the initial insulation resistance is lowered, and when the added amount of the second subcomponent is 0 mol ≦ the second subcomponent <4 mol, the added amount is large (3.8 mol). ), Early I
The occurrence of R defect rate can be reduced, and the added amount is small (0 mol)
It was confirmed that the capacity temperature change rate became smaller as the capacity became smaller.
The value of the initial IR failure rate is obtained by calculating the specific resistance ρ of about 100 capacitor samples from the insulation resistance IR, the electrode area and the thickness of the dielectric layer (4 μm in this embodiment), respectively. Dividing the number of samples by one or more digits smaller than the value of resistivity ρ in the bulk state by the total number,
Shown as a percentage. As this value is smaller, the initial I
The R defect rate is low, and there are many non-defective products.

Note that MnO was added in place of MnCO ₃ and evaluated under the same conditions as above, but the same results were obtained in each case.

Example 5 The main components m = 0.885, x = 0.36, y = 0, the first
The number of moles of the subcomponent (in terms of V) = 0.2 mole, the number of moles of the second subcomponent (in terms of Mn) = 0.37 mole, and the number of moles of the fourth subcomponent (in terms of Y) = 0.07 mole. In addition to the above, the addition amount of (SiO ₂ + CaO) as the third subcomponent was
The degree of improvement in the high temperature load life was tested by changing as shown in Table 6. Table 6 shows the results.

[0100]

[Table 6]

As shown in Table 6, the sinterability was improved by adding more than 0 mol of the third subcomponent. It was also confirmed that by setting the addition amount to less than 15 mol, a decrease in the relative dielectric constant was suppressed and a sufficient capacity could be secured. The value of the initial IR failure rate was determined in the same manner as in Example 4. Note that instead of (SiO ₂ + CaO), C
Similar results were obtained using aSiO ₃ .

Example 6 Samples (Samples 13-1 to 13-) were prepared in the same manner as Sample 13 of Example 1 shown in Table 4 except that the oxygen partial pressure in the firing step was changed as shown in Table 7. A plurality of 3) were prepared, and the occurrence rate of defects in the initial insulation resistance (IR) of these samples was calculated. The value of the initial IR failure rate was determined in the same manner as in Example 4. Table 7 shows the results.

[0103]

[Table 7]

As shown in Table 7, the oxygen partial pressure was 10
^When prepared at ^-6 Pa or more, it was confirmed that the effect of reducing the initial IR defect rate was particularly observed. Table 7
The samples 13-1 to 13-3 are all examples of the present invention.

Example 7 The oxygen partial pressure in the heat treatment step was 3.54 × 10 ⁻² P
3. a (900 ° C, 9 hours, wetter temperature 35 ° C);
23 × 10 ⁻¹ Pa (1100 ° C., 3 hours, wetter temperature 35 ° C.), and the thickness of the dielectric layer was 9 μm (sample 27).
28), a plurality of samples were prepared in the same manner as Sample 12 shown in Table 4 except that the sample was different from 4 μm (Samples 29 to 30). Calculated. The results are shown in FIGS. 9 (A) and 9 (B).
As shown in FIG. 9, when the thickness of the dielectric layer is as large as 9 μm, the difference in oxygen partial pressure does not affect the defect occurrence rate (FIG. 9).
(See (A).) When the thickness becomes as thin as 4 μm, the oxygen partial pressure becomes 10
^-4 Pa or more ^{(incidentally,} are also within the scope of 10 -1 10 Pa) is 4.23 × ¹⁰ -1 Pa (Sample 30)
It can be confirmed that the effect when the adjustment is made is obtained (FIG. 9).
(B)). The value of the initial IR failure rate was determined in the same manner as in Example 4. In addition, the oxygen partial pressure in the heat treatment step was set to 9.61 × 10 ⁻² Pa (1100 ° C., 3 hours, wetter temperature 0 ° C.), and the effect of reducing the occurrence of the defective rate of the initial insulation resistance was similar to the samples 27 to 30. (Samples 31 to 32), no such effect was observed. From this, it is considered that the holding temperature does not contribute to the reduction of the defect occurrence rate of the initial insulation resistance of the sample, but the oxygen partial pressure during the heat treatment contributes.

Example 8 As shown in Table 8, as the fourth component, Y, Sc, Ce,
Dy, Ho, Er, Tm, Yb, Lu, Tb, Gd, E
0.07 mol of each oxide of u, Sm, La, Pr, Nd and Pm is added in terms of the rare earth element in the oxide, and annealing is performed at a holding temperature of 1100 ° C., a holding time of 3 hours, and humidification. A plurality of samples were prepared in the same manner as in Sample 13 except that the test was performed in a N ₂ gas atmosphere (oxygen partial pressure was 4.23 × 10 ⁻¹ Pa), and defective initial insulation resistance (IR) of these samples occurred. The rate was calculated. Table 8 shows the results.

[0107]

[Table 8]

From the results shown in Table 8, Y, Sc, C
When oxides of e, Dy, Ho, Er, Tm, Yb and Lu are added (Samples 13-4 to 13-12), Tb, Gd, Eu, Sm, La, Pr, Nd and Pm When an oxide is added (Samples 13-13 to 1
Compared with 3-20), it was confirmed that the yield rate of the initial insulation resistance (IR) was improved, that is, the defective rate of the initial IR when the layer was thinned could be significantly reduced.

[0109]Example 9 The third subcomponent is (SiO 2₂+ CaO) = (0.4+
0.4) mol (p = 0), (SiO₂+ CaO + Sr
O) = (0.4 + 0.2 + 0.2) mol (p = 0.
5) and (SiO₂+ SrO) = (0.4 + 0.
4) mole (p = 1) and annealing at a holding temperature
1100 ° C., temperature holding time 3 hours, humidified N ₂gas
Atmosphere (oxygen partial pressure is 4.23 × 10^-1Pa)
Otherwise, duplicate the capacitor sample in the same manner as Sample 13.
Several pieces were prepared (samples 33, 34, 35). And the third
(Sr as a subcomponent_p, Ca_1-p) SiO₃
In the above, the content ratio of Sr
The initial insulation resistance (IR) depends on the yield rate
I gave or evaluated. The results are shown in FIG. Shown in FIG.
From the results, it can be seen that as the content ratio of Sr increases, the initial I
75% (sample 33), 83% (sample 3)
4), 100% (sample 35)
The initial IR defect rate has dropped to 25%, 17% and 0%
Was confirmed. The value of the defect rate of the initial IR is
It was determined in the same manner as in Example 4.

[0110]

As described above, according to the present invention, it is possible to improve the resistance to reduction during sintering, to have excellent capacity-temperature characteristics after sintering, and to improve the accelerated life of insulation resistance. The dielectric ceramic composition which can be provided can be provided. Further, according to the present invention, it is possible to provide an electronic component such as a chip capacitor having excellent capacitance-temperature characteristics, improved acceleration life of insulation resistance, and improved reliability. Furthermore, according to the present invention, it has excellent capacitance-temperature characteristics, while maintaining the reliability required for electronic components, even when the dielectric layer is thinned, the insulation resistance is hardly deteriorated, and the initial insulation resistance is reduced. A method of manufacturing an electronic component such as a chip capacitor having a low defect rate can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a multilayer ceramic capacitor according to an embodiment of the present invention.

FIG. 2 is a graph showing capacitance-temperature characteristics of Sample 13 which is an example of the present invention.

FIG. 3 is a TEM photograph of Sample 3 which is an example of the present invention.

FIG. 4 is a diagram showing a particle in Sample 3 which is an example of the present invention.
Distance from the world and Y₂ O₃Graph showing the relationship with the concentration of
It is.

FIG. 5 is a TEM photograph of Sample 9 which is an example of the present invention.

FIG. 6 is a diagram showing a particle in sample 9 according to an embodiment of the present invention.
Distance from the world and Y₂ O₃Graph showing the relationship with the concentration of
It is.

FIG. 7 is a graph showing the relationship between the presence or absence of Y as a fourth subcomponent and the high-temperature load life.

FIG. 8 is a graph showing the relationship between the added amount of V and the high-temperature load life time in Samples 12 and 13 which are examples of the present invention.

FIGS. 9A and 9B are graphs showing the relationship between the oxygen partial pressure in the heat treatment step and the yield rate of the initial insulation resistance when the thickness of the dielectric layer is changed.

FIG. 10 shows (Sr _p ,
Content of Sr in Ca _1-p ) SiO ₃ ,
5 is a graph showing the relationship between the initial insulation resistance (IR) of a capacitor sample and the yield rate.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 multilayer ceramic capacitor 10 capacitor element body 2 dielectric layer 3 internal electrode layer 4 external electrode

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Mikio Takahashi 1-1-13 Nihonbashi, Chuo-ku, Tokyo TDK Corporation (72) Inventor Yo Yo Sato 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK In-house F term (reference) 4G031 AA01 AA02 AA03 AA04 AA05 AA06 AA07 AA08 AA09 AA11 AA12 AA13 AA14 AA15 AA17 AA18 AA19 AA28 AA30 AA39 CA03 GA17 5E001 AB03 AE01 AE03 AF06 AB01 CB01 CB22 CB26 CB30 CB32 CB33 CB35 CB36 CB37 CB39 CB40 CB41 CB42

Claims (15)

[Claims] [Claim 1] ｒ (Sr_1-xCa_x) O｝_m・
(Ti_1-yZr _y) O₂Dielectric of composition shown by
A main component including a body oxide, and an oxide of R (where R is Sc, Y, La, Ce, P
r, Nd, Pm, Sm, Eu, Gd, Tb, Dy, H
o, Er, Tm, Yb and Lu
Having at least a fourth subcomponent containing at least one
A symbol m indicating a composition molar ratio in a formula contained in the main component, which is a body porcelain composition;
x and y have a relationship of 0.94 <m <1.02, 0 ≦ x ≦ 1.00, 0 ≦ y ≦ 0.20, and a ratio of the fourth subcomponent to 100 mol of the main component
Is 0.02 mol ≦ the fourth subcomponent <in terms of R in the oxide <
A dielectric porcelain composition that is 2 moles. 2. The dielectric material according to claim 1, wherein the oxide of R contained in the fourth subcomponent is at least one oxide of Sc, Y, Ce, Dy, Ho, Er, Tm, Yb, and Lu. Body porcelain composition. 3. The dielectric porcelain composition according to claim 1, wherein the oxide of R contained in the fourth subcomponent contains particles distributed substantially uniformly in the particles. 4. The method according to claim 1, further comprising a first subcomponent containing at least one selected from oxides of V, Nb, W, Ta, and Mo and / or compounds that become these oxides after firing. The dielectric porcelain composition according to any one of claims 1 to 3, wherein a ratio of the first subcomponent to mol is 0.01 mol ≦ first subcomponent <2 mol in terms of a metal element in the oxide. . 5. The method according to claim 1, further comprising a second subcomponent containing an oxide of Mn and / or a compound that becomes an oxide of Mn by firing, wherein a ratio of the second subcomponent to 100 mol of the main component is in the oxide. 0 mol ≦ second subcomponent <
The dielectric ceramic composition according to any one of claims 1 to 4, wherein the amount is 4 mol. 6. SiO ₂ , MO (where M is B
a, Ca, at least one element selected from Sr and Mg), further comprising a third subcomponent including at least one selected from Li ₂ O and _B 2 _{O 3,} wherein with respect to 100 moles of the main first The dielectric ceramic composition according to any one of claims 1 to 5, wherein a ratio of the three subcomponents is 0 mol <third subcomponent <15 mol in terms of oxide. 7. (Sr _p , Ca _1-p ) SiO ₃
(Where p is 0.3 ≦ p ≦ 1), and the ratio of the third subcomponent to 100 mol of the main component is 0 mol <third subcomponent in terms of oxide. The dielectric ceramic composition according to any one of claims 1 to 5, wherein the component is <15 mol. 8. A capacitance change rate with respect to temperature (ΔC)
Is at least within the temperature range of 20 to 85 ° C.,
The dielectric ceramic composition according to any one of claims 1 to 7, wherein the dielectric ceramic composition has a temperature of 2000 to 0 ppm / ° C (the reference temperature of the capacitance C is 20 ° C). 9. An electronic component having a dielectric layer, wherein the dielectric layer is made of a dielectric porcelain composition, and the dielectric porcelain composition is ｛(Sr _1-x Ca _x )
_{O} m · (Ti 1- y} Zr y) and the main component containing a dielectric oxide of a composition represented by _{O 2,} oxides of R (wherein, R is, Sc, Y, La, Ce , P
r, Nd, Pm, Sm, Eu, Gd, Tb, Dy, H
o, Er, Tm, at least one selected from Yb and Lu), and a fourth subcomponent containing at least a symbol m indicating a composition molar ratio in a formula contained in the main component,
x and y are in the relationship of 0.94 <m <1.02, 0 ≦ x ≦ 1.00, 0 ≦ y ≦ 0.20, and the ratio of the fourth subcomponent to 100 mol of the main component is 0.02 mol ≦ the fourth subcomponent <in terms of R in the oxide <
Electronic components that are 2 moles. 10. The electron according to claim 9, wherein the oxide of R contained in the fourth subcomponent is at least one oxide of Sc, Y, Ce, Dy, Ho, Er, Tm, Yb, and Lu. parts. 11. A capacitor element main body in which said dielectric layers and internal electrode layers are alternately stacked together.
Or the electronic component according to 10. 12. The electronic component according to claim 11, wherein the conductive material contained in the internal electrode layer is nickel or a nickel alloy. 13. {(Sr _1-x Ca _x ) O} _m
· A main component containing a _{(Ti 1-y} Zr _y) dielectric oxide having a composition represented by _{O 2,} oxides of R (wherein, R is, Sc, Y, La, Ce , P
r, Nd, Pm, Sm, Eu, Gd, Tb, Dy, H
o, Er, Tm, at least one selected from Yb and Lu), and a fourth subcomponent containing at least a symbol m indicating a composition molar ratio in a formula contained in the main component,
x and y are in the relationship of 0.94 <m <1.02, 0 ≦ x ≦ 1.00, 0 ≦ y ≦ 0.20, and the ratio of the fourth subcomponent to 100 mol of the main component is 0.02 mol ≦ the fourth subcomponent <in terms of R in the oxide <
A step of preparing a dielectric paste using the dielectric porcelain composition of 2 mol; a step of preparing an internal electrode paste; and alternately laminating the dielectric paste and the internal electrode paste to obtain a laminate. And a step wherein the oxygen partial pressure is 10 ⁻¹⁰ to 10 ⁻³ Pa.
A method of manufacturing an electronic component, comprising: a firing step of obtaining a sintered body by firing in an atmosphere of (1); 14. {(Sr _1-x Ca _x ) O} _m
· A main component containing a _{(Ti 1-y} Zr _y) dielectric oxide having a composition represented by _{O 2,} oxides of R (wherein, R is, Sc, Y, La, Ce , P
r, Nd, Pm, Sm, Eu, Gd, Tb, Dy, H
o, Er, Tm, at least one selected from Yb and Lu), and a fourth subcomponent containing at least a symbol m indicating a composition molar ratio in a formula contained in the main component,
x and y are in the relationship of 0.94 <m <1.02, 0 ≦ x ≦ 1.00, 0 ≦ y ≦ 0.20, and the ratio of the fourth subcomponent to 100 mol of the main component is 0.02 mol ≦ the fourth subcomponent <in terms of R in the oxide <
A step of preparing a dielectric paste using the dielectric porcelain composition of 2 mol; a step of preparing an internal electrode paste; and alternately laminating the dielectric paste and the internal electrode paste to obtain a laminate. A method for producing an electronic component, comprising: a step of: sintering the laminate to obtain a sintered body; and heat-treating the sintered body in an atmosphere having an oxygen partial pressure of 10 ⁻⁴ Pa or more. 15. The internal electrode paste according to claim 13, wherein nickel or a nickel alloy is used.
A method for manufacturing the electronic component described in the above.